Question

Решите систему уравнений
y-x=-3
X^2-y^2=63

Answer 1

y-x=3
x^2-y^2=63
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y-x=-3
y=-3+x
x^2-(-3+x)^2=63
x^2-(x-3)^2=63
x^2-(x^2-6x+9)=63
x^2-x^2+6x-9=63
6x=72
x=12
y=-3+12=9